Greetings! I'm working on a vintage car that had (when I disassembled it many years ago) an adaptor to mate a vacuum hard line to the intake manifold. After searching too long, I'm going to declare the adaptor lost and try to make a replacement. The hard line is 3/8" steel, double flared and fitted with a copper-tubing-style compression ferrule. The flare nut is 9/16-24. The intake manifold is tapped 1/8-27 NPTF.

I know how to make the 1/8-27 male end of the adaptor, and also the female 9/16-24 thread. I'm less clear on how to make the angled seat for the ferrule. I believe the included angle between the tapered faces is 140 degrees. That's pretty close to the standard drill point of 135 degrees. I see two ways to go about it: 1) re-grind a drill to the desired angle and reduce the rake of the leading edge so it will leave a smooth surface, or 2) make a D-bit with the desired angle.

Any suggestions?

08-13-2019, 03:35 PM

CPeter

That sounds like a standard brake line fitting. I used them on my old Ford Flathead trucks.
Peter

08-13-2019, 05:03 PM

andywander

Are there actually flare connections that use ferrules?

08-13-2019, 05:15 PM

Corbettprime

I don't believe a brake line double flare uses a copper compression ferrule. Just a flare nut. My old Papco flaring tool will do double flares, but its a lot of trouble, and easier to buy a premade line. Oops, just noticed it's for a vacuum line. A ferrule alone should suffice.

08-13-2019, 05:36 PM

alsinaj

You are right -- the line isn't flared, since it uses a ferrule. I was thinking of another line there is a little problem with.

CPeter: do you know a source that carries those particular brake fittings?

08-13-2019, 06:09 PM

Joel

You shall surely find the old one soon after making the new one. It will come out of hiding as soon as it knows it's safe...

08-13-2019, 10:15 PM

alsinaj

Joel,

True, but experience tells me that to find the original I must first make a replica. So my question stands.

JA

08-14-2019, 01:05 PM

Video Man

I made an adapter (air line for a narrow gauge loco, immaterial....) by boring the seat using the compound on my lathe and a small boring bar...just a thought....